The productivity of a welding shop is a combination of several factors and may thus be expressed in several ways, especially in the form of a deposition rate, that is to say the amount of material deposited in one hour by a welder, said amount of material corresponding to the amount of consumable wire used to produce the welded joint.
Current, wire speed, welding speed or shop efficiency parameters are all related to the efficiency of the welding.
If we consider that the size of the weld beads produced meets the specifications, then by increasing the wire speed, and therefore the current for the process, the rate of displacement of the arc is increased, which therefore means a longer weld bead deposited per unit time.
Likewise, any increase in the level of utilization of the shop or in the effective time during which the arc is ignited will have a favorable impact on the deposition rate of the shop.
The efficiency of a welding shop may be improved provided that there are suitable diagnostic and monitoring tools for identifying the causes of inefficiencies, such as too low a wire speed, too low a current, too low a level of utilization of the welding machines, too short an effective arc ignition time, etc.
At the present time, lacking a suitable measurement or monitoring system, most manual welding professionals use the total manufacturing time or the number of workpieces produced, over a given time period, as parameters for producing estimates, for defining the overall scheduling of the welding shop and above all to try to improve the productivity of their welding processes.
Unfortunately, using only such parameters it is not possible to take into account the actual utilization of the welding process, the efficiency of which depends not only on the duty factor of the process, namely the ratio of the time during which the electric welding arc is ignited to the total work time, but also on optimizing the welding parameters, when the arc is in operation, such as voltage, wire speed, current, type of gas mixture used and flow rate of the shielding gas used, angle of the torch with respect to the workpiece to be welded, direction of displacement, cleanliness of the workpieces, etc.
To improve the productivity of the shop, to produce accurate estimates and to manage the scheduling of the shop, it is therefore necessary to have accurate measurable values that are directly connected to the actual welding activity.
Although at the present time product shop management software products are commercially available, it turns out that these do not make it possible for measurable and reliable data that directly reflect the welding activity to be obtained automatically.
There are also what are called “multiparameter” measurement systems that extract measurable data associated with the process (current, voltage, wire speeds, etc.) and use them for traceability and quality assurance purposes, but not for strictly speaking managing and improving a welding shop in which several torches are employed simultaneously by different operators.
In addition, these multiparameter systems necessarily employ several sensors for measuring the desired data, in particular the current, the voltage, the wire speed and the gas flow rate. However, it turns out that the cost of all these sensors and the system that uses them is usually high and therefore often dissuasive.
In short, all the systems that currently exist are too complex and/or their cost is several times greater than that acceptable from the industrial standpoint and/or give only mediocre or imperfect results.
At the present time, there are no simple and economical systems for the effective management of a welding shop in which several torches are employed simultaneously by different operators, that is to say one for making the link between a measured parameter and the management elements of the shop, namely the duty factor and/or the deposition rate.